What Is This Hazardous Substance Site Near Portage Creek in Kalamazoo?

Located on the edge of the Portage Creek between Cork and Alcott Streets in Kalamazoo, is a site that looks like it could be a park but looks can be deceiving. This site in Kalamazoohas signs all the way around that say "HAZARDOUS SUBSTANCE" and warn to stay out. What is in there? Why is there no description of who owns it on Google Maps or even the county web site. And why is it so close to the Portage Creek? Perhaps it's part of the Kalamazoo Superfund Site.